The XDetector GUI is used for viewing EIS data as detector images. If the raster contains lines on both detectors, two xdetector windows, one for each CCD will pop up. The xdetector interface will look something like the image below, where two line windows each of 256 pixels width are displayed on CCD A. This raster contains is a test pattern from negineering tests at MSSL. The abscissa in the image is wavelength (here shown as pixel numbers) and the ordinate axis is position along the slit (again in pixels). Slit position could for real data translate to Solar-Y position.